Add support for direct binding evaluation in QV4Script

This way there is no need to rewrite the binding expressions
anymore, instead we can directly compile them into a
binding function.

Change-Id: I91a0c540d066976e363590fe9ccde6a81ee92b1d
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

8 files changed, 159 insertions, 198 deletions

diff --git a/src/qml/qml/qqmlbinding.cpp b/src/qml/qml/qqmlbinding.cpp
index b66f053b0f..936c63f35e 100644
--- a/src/qml/qml/qqmlbinding.cpp
+++ b/src/qml/qml/qqmlbinding.cpp
@@ -108,11 +108,8 @@ QQmlBinding::QQmlBinding(const QString &str, QObject *obj, QQmlContext *ctxt)
     QQmlAbstractExpression::setContext(QQmlContextData::get(ctxt));
     setScopeObject(obj);
 
-    QQmlRewrite::RewriteBinding rewriteBinding;
-    QString code = rewriteBinding(str);
-
     m_expression = str.toUtf8();
-    v4function = evalFunction(context(), obj, code, QString(), 0);
+    v4function = qmlBinding(context(), obj, str, QString(), 0);
 }
 
 QQmlBinding::QQmlBinding(const QQmlScriptString &script, QObject *obj, QQmlContext *ctxt)
@@ -146,11 +143,6 @@ QQmlBinding::QQmlBinding(const QQmlScriptString &script, QObject *obj, QQmlConte
         }
     }
 
-    if (needRewrite) {
-        QQmlRewrite::RewriteBinding rewriteBinding;
-        code = rewriteBinding(scriptPrivate->script);
-    }
-
     setNotifyOnValueChanged(true);
     QQmlAbstractExpression::setContext(QQmlContextData::get(ctxt ? ctxt : scriptPrivate->context));
     setScopeObject(obj ? obj : scriptPrivate->scope);
@@ -159,7 +151,10 @@ QQmlBinding::QQmlBinding(const QQmlScriptString &script, QObject *obj, QQmlConte
     m_lineNumber = scriptPrivate->lineNumber;
     m_columnNumber = scriptPrivate->columnNumber;
 
-    v4function = evalFunction(context(), scopeObject(), code, QString(), m_lineNumber);
+    if (needRewrite)
+        v4function = qmlBinding(context(), scopeObject(), code, QString(), m_lineNumber);
+    else
+        v4function = evalFunction(context(), scopeObject(), code, QString(), m_lineNumber);
 }
 
 QQmlBinding::QQmlBinding(const QString &str, QObject *obj, QQmlContextData *ctxt)
@@ -170,11 +165,8 @@ QQmlBinding::QQmlBinding(const QString &str, QObject *obj, QQmlContextData *ctxt
     QQmlAbstractExpression::setContext(ctxt);
     setScopeObject(obj);
 
-    QQmlRewrite::RewriteBinding rewriteBinding;
-    QString code = rewriteBinding(str);
-
     m_expression = str.toUtf8();
-    v4function = evalFunction(ctxt, obj, code, QString(), 0);
+    v4function = qmlBinding(ctxt, obj, str, QString(), 0);
 }
 
 QQmlBinding::QQmlBinding(const QString &str, bool isRewritten, QObject *obj,
@@ -187,17 +179,12 @@ QQmlBinding::QQmlBinding(const QString &str, bool isRewritten, QObject *obj,
     QQmlAbstractExpression::setContext(ctxt);
     setScopeObject(obj);
 
-    QString code;
-    if (isRewritten) {
-        code = str;
-    } else {
-        QQmlRewrite::RewriteBinding rewriteBinding;
-        code = rewriteBinding(str);
-    }
-
     m_expression = str.toUtf8();
 
-    v4function = evalFunction(ctxt, obj, code, url, m_lineNumber);
+    if (isRewritten)
+        v4function = evalFunction(ctxt, obj, str, url, m_lineNumber);
+    else
+        v4function = qmlBinding(ctxt, obj, str, url, m_lineNumber);
 }
 
 /*!
diff --git a/src/qml/qml/qqmlexpression.cpp b/src/qml/qml/qqmlexpression.cpp
index 32dbbb0e6c..419ea86ad9 100644
--- a/src/qml/qml/qqmlexpression.cpp
+++ b/src/qml/qml/qqmlexpression.cpp
@@ -96,42 +96,6 @@ void QQmlExpressionPrivate::init(QQmlContextData *ctxt, const QString &expr,
     setScopeObject(me);
 }
 
-void QQmlExpressionPrivate::init(QQmlContextData *ctxt, const QByteArray &expr,
-                                 bool isRewritten, QObject *me, const QString &srcUrl,
-                                 quint16 lineNumber, quint16 columnNumber)
-{
-    url = srcUrl;
-    line = lineNumber;
-    column = columnNumber;
-
-    if (isRewritten) {
-        expressionFunctionValid = true;
-        expressionFunctionRewritten = true;
-        v8function = evalFunction(ctxt, me, expr.constData(), expr.length(),
-                                  srcUrl, lineNumber, &v8qmlscope);
-        setUseSharedContext(false);
-
-        expressionUtf8 = expr;
-    } else {
-        expression = QString::fromUtf8(expr);
-
-        expressionFunctionValid = false;
-        expressionFunctionRewritten = isRewritten;
-    }
-
-    QQmlAbstractExpression::setContext(ctxt);
-    setScopeObject(me);
-}
-
-QQmlExpression *
-QQmlExpressionPrivate::create(QQmlContextData *ctxt, QObject *object,
-                              const QString &expr, bool isRewritten,
-                              const QString &url, quint16 lineNumber, quint16 columnNumber)
-{
-    return new QQmlExpression(ctxt, object, expr, isRewritten, url, lineNumber, columnNumber,
-                              *new QQmlExpressionPrivate);
-}
-
 /*!
     \class QQmlExpression
     \since 5.0
@@ -174,29 +138,6 @@ QQmlExpression::QQmlExpression()
 {
 }
 
-/*!  \internal */
-QQmlExpression::QQmlExpression(QQmlContextData *ctxt,
-                                               QObject *object, const QString &expr, bool isRewritten,
-                                               const QString &url, int lineNumber, int columnNumber,
-                                               QQmlExpressionPrivate &dd)
-: QObject(dd, 0)
-{
-    Q_D(QQmlExpression);
-    d->init(ctxt, expr, isRewritten, object, url, qmlSourceCoordinate(lineNumber), qmlSourceCoordinate(columnNumber));
-}
-
-/*!  \internal */
-QQmlExpression::QQmlExpression(QQmlContextData *ctxt,
-                                               QObject *object, const QByteArray &expr,
-                                               bool isRewritten,
-                                               const QString &url, int lineNumber, int columnNumber,
-                                               QQmlExpressionPrivate &dd)
-: QObject(dd, 0)
-{
-    Q_D(QQmlExpression);
-    d->init(ctxt, expr, isRewritten, object, url, qmlSourceCoordinate(lineNumber), qmlSourceCoordinate(columnNumber));
-}
-
 /*!
     Create a QQmlExpression object that is a child of \a parent.
 
@@ -271,15 +212,6 @@ QQmlExpression::QQmlExpression(QQmlContextData *ctxt, QObject *scope,
     d->init(ctxt, expression, scope);
 }
 
-/*!  \internal */
-QQmlExpression::QQmlExpression(QQmlContextData *ctxt, QObject *scope,
-                                               const QString &expression, QQmlExpressionPrivate &dd)
-: QObject(dd, 0)
-{
-    Q_D(QQmlExpression);
-    d->init(ctxt, expression, scope);
-}
-
 /*!
     Destroy the QQmlExpression instance.
 */
@@ -314,11 +246,7 @@ QQmlContext *QQmlExpression::context() const
 QString QQmlExpression::expression() const
 {
     Q_D(const QQmlExpression);
-    if (!d->expressionUtf8.isEmpty()) {
-        return QString::fromUtf8(d->expressionUtf8);
-    } else {
-        return d->expression;
-    }
+    return d->expression;
 }
 
 /*!
@@ -330,7 +258,6 @@ void QQmlExpression::setExpression(const QString &expression)
 
     d->resetNotifyOnValueChanged();
     d->expression = expression;
-    d->expressionUtf8.clear();
     d->expressionFunctionValid = false;
     d->expressionFunctionRewritten = false;
 }
@@ -339,17 +266,10 @@ void QQmlExpression::setExpression(const QString &expression)
 v8::Handle<v8::Value> QQmlExpressionPrivate::v8value(bool *isUndefined)
 {
     if (!expressionFunctionValid) {
-        bool ok = true;
-
-        QQmlRewrite::RewriteBinding rewriteBinding;
-        rewriteBinding.setName(name);
-        QString code;
         if (expressionFunctionRewritten)
-            code = expression;
+            v8function = evalFunction(context(), scopeObject(), expression, url, line, &v8qmlscope);
         else
-            code = rewriteBinding(expression, &ok);
-
-        if (ok) v8function = evalFunction(context(), scopeObject(), code, url, line, &v8qmlscope);
+            v8function = qmlBinding(context(), scopeObject(), expression, url, line, &v8qmlscope);
         setUseSharedContext(false);
         expressionFunctionValid = true;
     }
diff --git a/src/qml/qml/qqmlexpression.h b/src/qml/qml/qqmlexpression.h
index b04abc1b98..b702a37ee0 100644
--- a/src/qml/qml/qqmlexpression.h
+++ b/src/qml/qml/qqmlexpression.h
@@ -91,14 +91,6 @@ public:
 Q_SIGNALS:
     void valueChanged();
 
-protected:
-    QQmlExpression(QQmlContextData *, QObject *, const QString &,
-                           QQmlExpressionPrivate &dd);
-    QQmlExpression(QQmlContextData *, QObject *, const QString &, bool,
-                           const QString &, int, int, QQmlExpressionPrivate &dd);
-    QQmlExpression(QQmlContextData *, QObject *, const QByteArray &, bool,
-                           const QString &, int, int, QQmlExpressionPrivate &dd);
-
 private:
     QQmlExpression(QQmlContextData *, QObject *, const QString &);
 
diff --git a/src/qml/qml/qqmlexpression_p.h b/src/qml/qml/qqmlexpression_p.h
index 4577878290..0c407a2367 100644
--- a/src/qml/qml/qqmlexpression_p.h
+++ b/src/qml/qml/qqmlexpression_p.h
@@ -80,7 +80,6 @@ public:
 
     void init(QQmlContextData *, const QString &, QObject *);
     void init(QQmlContextData *, const QString &, bool, QObject *, const QString &, quint16, quint16);
-    void init(QQmlContextData *, const QByteArray &, bool, QObject *, const QString &, quint16, quint16);
 
     QVariant value(bool *isUndefined = 0);
 
@@ -91,9 +90,6 @@ public:
 
     void _q_notify();
 
-    static QQmlExpression *create(QQmlContextData *, QObject *, const QString &, bool,
-                                  const QString &, quint16, quint16);
-
     bool expressionFunctionValid:1;
     bool expressionFunctionRewritten:1;
 
@@ -103,7 +99,6 @@ public:
     virtual void expressionChanged();
 
     QString expression;
-    QByteArray expressionUtf8;
 
     QV4::PersistentValue v8qmlscope;
     QV4::PersistentValue v8function;
diff --git a/src/qml/qml/qqmljavascriptexpression.cpp b/src/qml/qml/qqmljavascriptexpression.cpp
index b64035b66d..0e733cb1d2 100644
--- a/src/qml/qml/qqmljavascriptexpression.cpp
+++ b/src/qml/qml/qqmljavascriptexpression.cpp
@@ -306,7 +306,6 @@ void QQmlJavaScriptExpression::exceptionToError(const QV4::Exception &e, QQmlErr
     error.setDescription(e.value().toQString());
 }
 
-// Callee owns the persistent handle
 QV4::PersistentValue
 QQmlJavaScriptExpression::evalFunction(QQmlContextData *ctxt, QObject *scope,
                                        const char *code, int codeLength,
@@ -316,7 +315,6 @@ QQmlJavaScriptExpression::evalFunction(QQmlContextData *ctxt, QObject *scope,
     return evalFunction(ctxt, scope, QString::fromUtf8(code, codeLength), filename, line, qmlscope);
 }
 
-// Callee owns the persistent handle
 QV4::PersistentValue
 QQmlJavaScriptExpression::evalFunction(QQmlContextData *ctxt, QObject *scope,
                                        const QString &code, const QString &filename, quint16 line,
@@ -352,6 +350,41 @@ QQmlJavaScriptExpression::evalFunction(QQmlContextData *ctxt, QObject *scope,
     return result;
 }
 
+QV4::PersistentValue QQmlJavaScriptExpression::qmlBinding(QQmlContextData *ctxt, QObject *scope,
+                                                       const QString &code, const QString &filename, quint16 line,
+                                                       QV4::PersistentValue *qmlscope)
+{
+    QQmlEngine *engine = ctxt->engine;
+    QQmlEnginePrivate *ep = QQmlEnginePrivate::get(engine);
+
+    QV4::ExecutionEngine *v4 = QV8Engine::getV4(ep->v8engine());
+    QV4::ExecutionContext *ctx = v4->current;
+
+    QV4::Value scopeObject = ep->v8engine()->qmlScope(ctxt, scope)->v4Value();
+    QV4::Script script(v4, scopeObject.asObject(), code, filename, line);
+    QV4::Value result;
+    try {
+        script.parse();
+        result = script.qmlBinding();
+    } catch (QV4::Exception &e) {
+        e.accept(ctx);
+        QQmlError error;
+        QQmlExpressionPrivate::exceptionToError(e, error);
+        if (error.description().isEmpty())
+            error.setDescription(QLatin1String("Exception occurred during function evaluation"));
+        if (error.line() == -1)
+            error.setLine(line);
+        if (error.url().isEmpty())
+            error.setUrl(QUrl::fromLocalFile(filename));
+        ep->warning(error);
+        return QV4::PersistentValue();
+    }
+    if (qmlscope)
+        *qmlscope = scopeObject;
+    return result;
+}
+
+
 void QQmlJavaScriptExpression::clearGuards()
 {
     while (Guard *g = activeGuards.takeFirst())
diff --git a/src/qml/qml/qqmljavascriptexpression_p.h b/src/qml/qml/qqmljavascriptexpression_p.h
index d7db55d4f6..caf1266415 100644
--- a/src/qml/qml/qqmljavascriptexpression_p.h
+++ b/src/qml/qml/qqmljavascriptexpression_p.h
@@ -155,6 +155,11 @@ public:
                                                      const char *code, int codeLength,
                                                      const QString &filename, quint16 line,
                                                      QV4::PersistentValue *qmlscope = 0);
+    // doesn't require rewriting the expression
+    static QV4::PersistentValue qmlBinding(QQmlContextData *ctxt, QObject *scope,
+                                        const QString &code,
+                                        const QString &filename, quint16 line,
+                                        QV4::PersistentValue *qmlscope = 0);
 protected:
     ~QQmlJavaScriptExpression();
 
diff --git a/src/qml/qml/v4/qv4script.cpp b/src/qml/qml/v4/qv4script.cpp
index fa63ed33cb..610e80246e 100644
--- a/src/qml/qml/v4/qv4script.cpp
+++ b/src/qml/qml/v4/qv4script.cpp
@@ -58,119 +58,140 @@
 
 using namespace QV4;
 
-struct FunctionWrapper : FunctionObject
+struct QmlBindingWrapper : FunctionObject
 {
-    FunctionWrapper(ExecutionContext *scope, Function *f)
+    QmlBindingWrapper(ExecutionContext *scope, Function *f, Object *qml)
         : FunctionObject(scope, scope->engine->id_eval)
+        , qml(qml)
     {
+        vtbl = &static_vtbl;
         function = f;
         usesArgumentsObject = function->usesArgumentsObject;
         needsActivation = function->needsActivation();
         defineReadonlyProperty(scope->engine->id_length, Value::fromInt32(1));
     }
+
+    static Value call(Managed *that, ExecutionContext *, const Value &, Value *, int);
+
+protected:
+    static const ManagedVTable static_vtbl;
+
+private:
+    Object *qml;
 };
 
+DEFINE_MANAGED_VTABLE(QmlBindingWrapper);
+
+Value QmlBindingWrapper::call(Managed *that, ExecutionContext *ctx, const Value &, Value *, int)
+{
+    ExecutionEngine *engine = ctx->engine;
+    QmlBindingWrapper *This = static_cast<QmlBindingWrapper *>(that);
+
+    ExecutionContext *qmlScope = engine->newQmlContext(This, This->qml);
+
+    Value result = This->function->code(qmlScope, This->function->codeData);
+
+    engine->popContext();
+
+    return result;
+
+}
+
 
 void Script::parse()
 {
     using namespace QQmlJS;
 
+    parsed = true;
+
     ExecutionEngine *v4 = scope->engine;
 
     MemoryManager::GCBlocker gcBlocker(v4->memoryManager);
 
     V4IR::Module module;
-    Function *globalCode = 0;
 
-    {
-        QQmlJS::Engine ee, *engine = &ee;
-        Lexer lexer(engine);
-        lexer.setCode(sourceCode, 1, false);
-        Parser parser(engine);
-
-        const bool parsed = parser.parseProgram();
-
-        DiagnosticMessage *error = 0, **errIt = &error;
-        foreach (const QQmlJS::DiagnosticMessage &m, parser.diagnosticMessages()) {
-            if (m.isError()) {
-                *errIt = new DiagnosticMessage;
-                (*errIt)->fileName = sourceFile;
-                (*errIt)->offset = m.loc.offset;
-                (*errIt)->length = m.loc.length;
-                (*errIt)->startLine = m.loc.startLine;
-                (*errIt)->startColumn = m.loc.startColumn;
-                (*errIt)->type = DiagnosticMessage::Error;
-                (*errIt)->message = m.message;
-                errIt = &(*errIt)->next;
-            } else {
-                qWarning() << sourceFile << ':' << m.loc.startLine << ':' << m.loc.startColumn
-                          << ": warning: " << m.message;
-            }
+    QQmlJS::Engine ee, *engine = &ee;
+    Lexer lexer(engine);
+    lexer.setCode(sourceCode, line, false);
+    Parser parser(engine);
+
+    const bool parsed = parser.parseProgram();
+
+    DiagnosticMessage *error = 0, **errIt = &error;
+    foreach (const QQmlJS::DiagnosticMessage &m, parser.diagnosticMessages()) {
+        if (m.isError()) {
+            *errIt = new DiagnosticMessage;
+            (*errIt)->fileName = sourceFile;
+            (*errIt)->offset = m.loc.offset;
+            (*errIt)->length = m.loc.length;
+            (*errIt)->startLine = m.loc.startLine;
+            (*errIt)->startColumn = m.loc.startColumn;
+            (*errIt)->type = DiagnosticMessage::Error;
+            (*errIt)->message = m.message;
+            errIt = &(*errIt)->next;
+        } else {
+            qWarning() << sourceFile << ':' << m.loc.startLine << ':' << m.loc.startColumn
+                      << ": warning: " << m.message;
         }
-        if (error)
-            scope->throwSyntaxError(error);
-
-        if (parsed) {
-            using namespace AST;
-            Program *program = AST::cast<Program *>(parser.rootNode());
-            if (!program) {
-                // if parsing was successful, and we have no program, then
-                // we're done...:
-                functionWrapper = Value::nullValue();
-                return;
-            }
-
-            QStringList inheritedLocals;
-            if (inheritContext)
-                for (String * const *i = scope->variables(), * const *ei = i + scope->variableCount(); i < ei; ++i)
-                    inheritedLocals.append(*i ? (*i)->toQString() : QString());
-
-            Codegen cg(scope, strictMode);
-            V4IR::Function *globalIRCode = cg(sourceFile, sourceCode, program, &module, QQmlJS::Codegen::EvalCode, inheritedLocals);
-            QScopedPointer<EvalInstructionSelection> isel(v4->iselFactory->create(v4, &module));
-            if (inheritContext)
-                isel->setUseFastLookups(false);
-            if (globalIRCode)
-                globalCode = isel->vmFunction(globalIRCode);
+    }
+    if (error)
+        scope->throwSyntaxError(error);
+
+    if (parsed) {
+        using namespace AST;
+        Program *program = AST::cast<Program *>(parser.rootNode());
+        if (!program) {
+            // if parsing was successful, and we have no program, then
+            // we're done...:
+            return;
         }
+
+        QStringList inheritedLocals;
+        if (inheritContext)
+            for (String * const *i = scope->variables(), * const *ei = i + scope->variableCount(); i < ei; ++i)
+                inheritedLocals.append(*i ? (*i)->toQString() : QString());
+
+        Codegen cg(scope, strictMode);
+        V4IR::Function *globalIRCode = cg(sourceFile, sourceCode, program, &module, QQmlJS::Codegen::EvalCode, inheritedLocals);
+        QScopedPointer<EvalInstructionSelection> isel(v4->iselFactory->create(v4, &module));
+        if (inheritContext)
+            isel->setUseFastLookups(false);
+        if (globalIRCode)
+            vmFunction = isel->vmFunction(globalIRCode);
     }
-    if (!globalCode)
+
+    if (!vmFunction)
         // ### FIX file/line number
         __qmljs_throw(v4->current, QV4::Value::fromObject(v4->newSyntaxErrorObject(v4->current, 0)), -1);
-
-    functionWrapper = Value::fromObject(new (v4->memoryManager) FunctionWrapper(scope, globalCode));
 }
 
 Value Script::run()
 {
-    if (functionWrapper.value().isNull())
-        return Value::undefinedValue();
-
-    if (functionWrapper.isEmpty())
+    if (!parsed)
         parse();
+    if (!vmFunction)
+        return Value::undefinedValue();
 
     QV4::ExecutionEngine *engine = scope->engine;
-    QV4::FunctionObject *f = functionWrapper.value().asFunctionObject();
 
     if (engine->debugger)
         engine->debugger->aboutToCall(0, scope);
 
     if (!qml) {
-        QV4::Function *function = this->function();
-        TemporaryAssignment<Function*> savedGlobalCode(engine->globalCode, function);
+        TemporaryAssignment<Function*> savedGlobalCode(engine->globalCode, vmFunction);
 
         bool strict = scope->strictMode;
         Lookup *lookups = scope->lookups;
 
-        scope->strictMode = function->isStrict;
-        scope->lookups = function->lookups;
+        scope->strictMode = vmFunction->isStrict;
+        scope->lookups = vmFunction->lookups;
 
         if (engine->debugger)
             engine->debugger->aboutToCall(0, scope);
 
         QV4::Value result;
         try {
-            result = function->code(scope, function->codeData);
+            result = vmFunction->code(scope, vmFunction->codeData);
         } catch (Exception &e) {
             scope->strictMode = strict;
             scope->lookups = lookups;
@@ -182,20 +203,24 @@ Value Script::run()
         return result;
 
     } else {
-        ExecutionContext *ctx = engine->newQmlContext(f, qml);
-
-        Value result = f->function->code(ctx, f->function->codeData);
-
-        engine->popContext();
-
-        return result;
+        FunctionObject *f = new (engine->memoryManager) QmlBindingWrapper(scope, vmFunction, qml);
+        return f->call(Value::undefinedValue(), 0, 0);
     }
 }
 
 Function *Script::function()
 {
-    FunctionObject *f = functionWrapper.value().asFunctionObject();
-    return f ? f->function : 0;
+    if (!parsed)
+        parse();
+    return vmFunction;
+}
+
+Value Script::qmlBinding()
+{
+    if (!parsed)
+        parse();
+    QV4::ExecutionEngine *v4 = scope->engine;
+    return Value::fromObject(new (v4->memoryManager) QmlBindingWrapper(scope, vmFunction, qml));
 }
 
 QV4::Value Script::evaluate(ExecutionEngine *engine,  const QString &script, Object *scopeObject)
diff --git a/src/qml/qml/v4/qv4script_p.h b/src/qml/qml/v4/qv4script_p.h
index 17b98c213d..b9d27a6be5 100644
--- a/src/qml/qml/v4/qv4script_p.h
+++ b/src/qml/qml/v4/qv4script_p.h
@@ -53,10 +53,10 @@ struct ExecutionContext;
 struct Q_QML_EXPORT Script {
     Script(ExecutionContext *scope, const QString &sourceCode, const QString &source = QString(), int line = 0, int column = 0)
         : sourceFile(source), line(line), column(column), sourceCode(sourceCode)
-        , scope(scope), strictMode(false), inheritContext(false), qml(0) {}
+        , scope(scope), strictMode(false), inheritContext(false), parsed(false), qml(0) {}
     Script(ExecutionEngine *engine, Object *qml, const QString &sourceCode, const QString &source = QString(), int line = 0, int column = 0)
         : sourceFile(source), line(line), column(column), sourceCode(sourceCode)
-        , scope(engine->rootContext), strictMode(true), inheritContext(true), qml(qml) {}
+        , scope(engine->rootContext), strictMode(true), inheritContext(true), parsed(false), qml(qml) {}
     QString sourceFile;
     int line;
     int column;
@@ -64,13 +64,17 @@ struct Q_QML_EXPORT Script {
     ExecutionContext *scope;
     bool strictMode;
     bool inheritContext;
+    bool parsed;
     Object *qml;
-    PersistentValue functionWrapper;
+    Function *vmFunction;
 
     void parse();
     Value run();
+    Value qmlBinding();
+
     Function *function();
 
+
     static Value evaluate(ExecutionEngine *engine, const QString &script, Object *scopeObject);
 };